FIG. 1 is a diagrammatic illustration of a wire bonding structure in accordance with a prior art. The typical wire bonding structure 10 comprises a substrate 11 and a die 13. The die 13 comprises an active surface 131 and a back surface 133, and is positioned on the top surface of the substrate 11. A bond pad 15 is positioned on the active surface 131 of the die 13, and connected with a lead 19 by means of a ball bond 171 and a bonding wire 173.
In the manufacturing process of wire bonding structure 10, the die 13 can be positioned on the top surface of the substrate 11 by means of an adhesive layer 12. For example, the back surface 133 of the die 13 can connect with the top surface of the substrate 11 via the adhesive layer 12. Thereafter, a capillary 18 can be used to form the ball bond 171 on the bond pad 15, and then form the bonding wire 173 to connect the ball bond 171 and the lead 19.
In general, the ball bond 171 and the bonding wire 173 are both made of copper, so that the cost of the manufacturing process of the bonding structure 10 can be reduced. However, damage to the die 13 or the bond pad 15 may occur during the bonding process. For example, heat can be generated when the ball bond 171 is formed on the bond pad 15, and in turn damage the die 13 and cause a reduction in the yield of the wire bonding structure 10.